Table 2.

Acute Outcomes Following Tdap Vaccination in Pregnancy By Interval Since Prior Tetanus-Containing Vaccination

	Time Since Prior Tetanus-Containing Vaccination, y						Relative Risk (95% CI)
	<2 (n = 4812)		2–5 (n = 9999)		>5 (Control) (n = 14 344)		<2 y vs Control		2–5 y vs Control
Outcome	No. of Patients	Ratea	No. of Patients	Ratea	No. of Patients	Ratea	Unadjustedb	Adjustedb,c	Unadjustedd	Adjustedc,d
Fever
0–3 d	1	2.1	0	0	5	3.5	0.60 (0.07–5.10)	0.66 (0.07–5.77)
0–7 d	3	6.2	1	1.0	6	4.2	1.49 (0.37–5.96)	1.61 (0.39–6.66)	0.24 (0.03–1.99)	0.21 (0.03–1.80)
Allergic Reaction
0–3 d	1	2.1	1	1.0	2	1.4	1.49 (0.14–16.4)	1.55 (0.13–18.45)	0.72 (0.07–7.91)	0.71 (0.06–8.13)
0–7 d	2	4.2	4	4.0	5	3.5	1.19 (0.23–6.14)	1.32 (0.24–7.17)	1.15 (0.31–4.27)	1.23 (0.32–4.80)
Local Reaction
0–3 d	2	4.2	7	7.0	16	11.2	0.37 (0.09–1.62)	0.49 (0.11–2.20)	0.63 (0.26–1.53)	0.77 (0.31–1.95)
0–7 d	6	12.5	17	17.0	22	15.3	0.81 (0.33–2.00)	1.01 (0.40–2.56)	1.11 (0.59–2.09)	1.28 (0.66–2.47)

Abbreviation: Tdap, tetanus, diphtheria, and acellular pertussis.

^aRate per10 000 women.

^bTdap + prior tetanus less than 2years before compared with Tdap + prior tetanus more than 5years before.

^cAdjusting for Vaccine Safety Datalink site and gestational age at vaccination in weeks.

^dTdap + prior tetanus 2 to 5years before compared with Tdap + prior tetanus more than 5 years before.